259 resultados para Belgian


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Pós-graduação em Agronomia (Horticultura) - FCA

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Scorpion toxins targeting voltage-gated sodium (NaV) channels are peptides that comprise 6076 amino acid residues cross-linked by four disulfide bridges. These toxins can be divided in two groups (a and beta toxins), according to their binding properties and mode of action. The scorpion a-toxin Ts2, previously described as a beta-toxin, was purified from the venom of Tityus serrulatus, the most dangerous Brazilian scorpion. In this study, seven mammalian NaV channel isoforms (rNaV1.2, rNaV1.3, rNaV1.4, hNaV1.5, mNaV1.6, rNaV1.7 and rNaV1.8) and one insect NaV channel isoform (DmNaV1) were used to investigate the subtype specificity and selectivity of Ts2. The electrophysiology assays showed that Ts2 inhibits rapid inactivation of NaV1.2, NaV1.3, NaV1.5, NaV1.6 and NaV1.7, but does not affect NaV1.4, NaV1.8 or DmNaV1. Interestingly, Ts2 significantly shifts the voltage dependence of activation of NaV1.3 channels. The 3D structure of this toxin was modeled based on the high sequence identity (72%) shared with Ts1, another T. serrulatus toxin. The overall fold of the Ts2 model consists of three beta-strands and one a-helix, and is arranged in a triangular shape forming a cysteine-stabilized a-helix/beta-sheet (CSa beta) motif.

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Iphisa elegans Gray, 1851 is a ground-dwelling lizard widespread over Amazonia that displays a broadly conserved external morphology over its range. This wide geographical distribution and conservation of body form contrasts with the expected poor dispersal ability of the species, the tumultuous past of Amazonia, and the previously documented prevalence of cryptic species in widespread terrestrial organisms in this region. Here we investigate this homogeneity by examining hemipenial morphology and conducting phylogenetic analyses of mitochondrial (CYTB) and nuclear (C-MOS) DNA sequence data from 49 individuals sampled across Amazonia. We detected remarkable variation in hemipenial morphology within this species, with multiple cases of sympatric occurrence of distinct hemipenial morphotypes. Phylogenetic analyses revealed highly divergent lineages corroborating the patterns suggested by the hemipenial morphotypes, including co-occurrence of different lineages. The degrees of genetic and morphological distinctness, as well as instances of sympatry among mtDNA lineages/morphotypes without nuDNA allele sharing, suggest that I. elegans is a complex of cryptic species. An extensive and integrative taxonomic revision of the I. elegans complex throughout its wide geographical range is needed. (c) 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 166, 361376.

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Context. Observations of transiting extrasolar planets are of key importance to our understanding of planets because their mass, radius, and mass density can be determined. These measurements indicate that planets of similar mass can have very different radii. For low-density planets, it is generally assumed that they are inflated owing to their proximity to the host-star. To determine the causes of this inflation, it is necessary to obtain a statistically significant sample of planets with precisely measured masses and radii. Aims. The CoRoT space mission allows us to achieve a very high photometric accuracy. By combining CoRoT data with high-precision radial velocity measurements, we derive precise planetary radii and masses. We report the discovery of CoRoT-19b, a gas-giant planet transiting an old, inactive F9V-type star with a period of four days. Methods. After excluding alternative physical configurations mimicking a planetary transit signal, we determine the radius and mass of the planet by combining CoRoT photometry with high-resolution spectroscopy obtained with the echelle spectrographs SOPHIE, HARPS, FIES, and SANDIFORD. To improve the precision of its ephemeris and the epoch, we observed additional transits with the TRAPPIST and Euler telescopes. Using HARPS spectra obtained during the transit, we then determine the projected angle between the spin of the star and the orbit of the planet. Results. We find that the host star of CoRoT-19b is an inactive F9V-type star close to the end of its main-sequence life. The host star has a mass M-* = 1.21 +/- 0.05 M-circle dot and radius R-* = 1.65 +/- 0.04 R-circle dot. The planet has a mass of M-P = 1.11 +/- 0.06 M-Jup and radius of R-P = 1.29 +/- 0.03 R-Jup. The resulting bulk density is only rho = 0.71 +/- 0.06 g cm (3), which is much lower than that for Jupiter. Conclusions. The exoplanet CoRoT-19b is an example of a giant planet of almost the same mass as Jupiter but a approximate to 30% larger radius.

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Objective. To compare the clinical, demographic, and serologic characteristics and the treatment of patients diagnosed with ankylosing spondylitis (AS) from Europe (EU) and Latin America (LA). Methods. We included 3439 patients from national registries: the Spanish Registry of Spondyloarthritis (REGISPONSER), the Belgian registry (ASPECT), and the Latin American Registry of Spondyloarthropathies (RESPONDIA). We selected patients with diagnosis of AS who met the modified New York classification criteria. Demographic, clinical, disease activity, functional, and metrological measurement data were recorded. Current treatment was recorded. The population was classified into 2 groups: patients with disease duration < 10 years and those with disease duration >= 10 years. A descriptive and comparative analysis of variables of both groups was carried out. Results. There were 2356 patients in EU group and 1083 in LA group. Prevalence of HLA-B27 was 71% in LA group and 83% in EU group (p < 0.001). We found a greater frequency of peripheral arthritis and enthesitis (p < 0.001) in the LA population; prevalence of arthritis was 57% in LA and 42% in EU, and for enthesitis, 54% and 38%. Except for treatment with anti-tumor necrosis factor (anti-TNF), the use of nonsteroidal antiinflammatory drugs (NSAID), corticosteroids, and disease-modifying antirheumatic drugs (DMARD), and the association of anti-TNF and methotrexate use showed a significant difference (p < 0.001) in the 2 populations. Conclusion. The principal differences in the clinical manifestations of patients with AS from EU and LA were the greater frequency of peripheral arthritis and enthesitis in LA group, the higher percentage of HLA-B27 in EU group, and the form of treatment, with a greater use of NSAID, steroids, and DMARD in the LA group. (First Release Nov 15 2012; J Rheumatol 2012;39:2315-20; doi:10.3899/jrheum.110687)

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Well determined radial velocities and abundances are essential for analyzing the properties of the globular cluster system of the Milky Way. However more than 50% of these clusters have no spectroscopic measure of their metallicity. In this context, this work provides new radial velocities and abundances for twenty Milky Way globular clusters which lack or have poorly known values for these quantities. The radial velocities and abundances are derived from spectra obtained at the Ca II triplet using the FORS2 imager and spectrograph at the VLT, calibrated with spectra of red giants in a number of clusters with well determined abundances. For about half of the clusters in our sample we present significant revisions of the existing velocities or abundances, or both. We also confirm the existence of a sizable abundance spread in the globular cluster M 54, which lies at the center of the Sagittarius dwarf galaxy. In addition evidence is provided for the existence of a small intrinsic internal abundance spread (sigma[Fe/H](int) approximate to 0.11-0.14 dex, similar to that of M 54) in the luminous distant globular cluster NGC 5824. This cluster thus joins the small number of Galactic globular clusters known to possess internal metallicity ([Fe/H]) spreads.

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CoRoT-21, a F8IV star of magnitude V = 16 mag, was observed by the space telescope CoRoT during the Long Run 01 ( LRa01) in the first winter field (constellation Monoceros) from October 2007 to March 2008. Transits were discovered during the light curve processing. Radial velocity follow-up observations, however, were performed mainly by the 10-m Keck telescope in January 2010. The companion CoRoT-21b is a Jupiter-like planet of 2.26 +/- 0.33 Jupiter masses and 1.30 +/- 0.14 Jupiter radii in an circular orbit of semi-major axis 0.0417 +/- 0.0011 AU and an orbital period of 2.72474 +/- 0.00014 days. The planetary bulk density is ( 1.36 +/- 0.48) x 10(3) kg m(-3), very similar to the bulk density of Jupiter, and follows an M-1/3 - R relation like Jupiter. The F8IV star is a sub-giant star of 1.29 +/- 0.09 solar masses and 1.95 +/- 0.2 solar radii. The star and the planet exchange extreme tidal forces that will lead to orbital decay and extreme spin-up of the stellar rotation within 800 Myr if the stellar dissipation is Q(*)/k2(*) <= 107.

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Documenting the Neotropical amphibian diversity has become a major challenge facing the threat of global climate change and the pace of environmental alteration. Recent molecular phylogenetic studies have revealed that the actual number of species in South American tropical forests is largely underestimated, but also that many lineages are millions of years old. The genera Phyzelaphryne (1 sp.) and Adelophryne (6 spp.), which compose the subfamily Phyzelaphryninae, include poorly documented, secretive, and minute frogs with an unusual distribution pattern that encompasses the biotic disjunction between Amazonia and the Atlantic forest. We generated >5.8 kb sequence data from six markers for all seven nominal species of the subfamily as well as for newly discovered populations in order to (1) test the monophyly of Phyzelaphryninae, Adelophryne and Phyzelaphryne, (2) estimate species diversity within the subfamily, and (3) investigate their historical biogeography and diversification. Phylogenetic reconstruction confirmed the monophyly of each group and revealed deep subdivisions within Adelophryne and Phyzelaphryne, with three major clades in Adelophryne located in northern Amazonia, northern Atlantic forest and southern Atlantic forest. Our results suggest that the actual number of species in Phyzelaphryninae is, at least, twice the currently recognized species diversity, with almost every geographically isolated population representing an anciently divergent candidate species. Such results highlight the challenges for conservation, especially in the northern Atlantic forest where it is still degraded at a fast pace. Molecular dating revealed that Phyzelaphryninae originated in Amazonia and dispersed during early Miocene to the Atlantic forest. The two Atlantic forest clades of Adelophryne started to diversify some 7 Ma minimum, while the northern Amazonian Adelophryne diversified much earlier, some 13 Ma minimum. This striking biogeographic pattern coincides with major events that have shaped the face of the South American continent, as we know it today. (C) 2012 Elsevier Inc. All rights reserved.

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We report the discovery by the CoRoT space mission of a new giant planet, CoRoT-20b. The planet has a mass of 4.24 +/- 0.23 M-Jup and a radius of 0.84 +/- 0.04 R-Jup. With a mean density of 8.87 +/- 1.10 g cm(-3), it is among the most compact planets known so far. Evolutionary models for the planet suggest a mass of heavy elements of the order of 800 M-circle plus if embedded in a central core, requiring a revision either of the planet formation models or both planet evolution and structure models. We note however that smaller amounts of heavy elements are expected by more realistic models in which they are mixed throughout the envelope. The planet orbits a G-type star with an orbital period of 9.24 days and an eccentricity of 0.56. The star's projected rotational velocity is v sin i = 4.5 +/- 1.0 km s(-1), corresponding to a spin period of 11.5 +/- 3.1 days if its axis of rotation is perpendicular to the orbital plane. In the framework of Darwinian theories and neglecting stellar magnetic breaking, we calculate the tidal evolution of the system and show that CoRoT-20b is presently one of the very few Darwin-stable planets that is evolving toward a triple synchronous state with equality of the orbital, planetary and stellar spin periods.

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La realizzazione di questa ricerca ha come obiettivo principe lo studio approfondito dell’istituto della riabilitazione penale all’interno del panorama legislativo italiano, con riferimento al contesto bolognese, e nella legislazione belga; inoltre si pone come scopo l’analisi dell’interazione autore-vittima del reato, con una particolare attenzione al risarcimento elargito alla persona offesa dal reato e alla figura della vittima prima nel sistema penale, poi nel procedimento specifico che porta alla riabilitazione del condannato. Il punto di partenza del lavoro di ricerca intrapreso è costituito da un’accurata ricerca bibliografica inerente agli argomenti trattati, al fine di poter approfondire una buona parte della letteratura italiana e belga esistente in materia. La fase successiva della ricerca è stata quella di reperire informazioni riguardanti l’ambito di studio da approfondire, cioè la riabilitazione, secondo una direttrice empirica. Pertanto, per quanto concerne la realtà italiana, sono stati analizzati, tramite una griglia di rilevazione costruita ad hoc, i fascicoli processuali relativi alla riabilitazione presenti negli archivi del Tribunale di Sorveglianza di Bologna (2004-2009); la situazione belga è invece stata studiata reperendo dati, riferiti alla réhabilitation pénal, rintracciati presso il “Service Public Fédéral Justice - Bureau Permanent Statistiques et Mesure de la charge de travail (BPSM)” (2008-2009), sia livello nazionale che delle cinque Corti di appello. Inoltre, al fine di ottenere un ulteriore punto di vista empirico riguardante l’istituto della riabilitazione penale, sono state effettuate delle interviste semi-strutturate al Presidente del Tribunale di Sorveglianza Dott. Francesco Maisto e al Sostituto Procuratore Generale di Liège Mr. Nicolas Banneux. Infatti l’esperienza lavorativa e il particolare ruolo ricoperto da questi “osservatori privilegiati”, competenti di riabilitazione e particolarmente sensibili alle tematiche criminologiche e vittimologiche, li pone direttamente in contatto con l’istituto e la procedura della riabilitazione, determinando in loro una profonda padronanza dell’oggetto di ricerca.

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This research has focused on the study of the behavior and of the collapse of masonry arch bridges. The latest decades have seen an increasing interest in this structural type, that is still present and in use, despite the passage of time and the variation of the transport means. Several strategies have been developed during the time to simulate the response of this type of structures, although even today there is no generally accepted standard one for assessment of masonry arch bridges. The aim of this thesis is to compare the principal analytical and numerical methods existing in literature on case studies, trying to highlight values and weaknesses. The methods taken in exam are mainly three: i) the Thrust Line Analysis Method; ii) the Mechanism Method; iii) the Finite Element Methods. The Thrust Line Analysis Method and the Mechanism Method are analytical methods and derived from two of the fundamental theorems of the Plastic Analysis, while the Finite Element Method is a numerical method, that uses different strategies of discretization to analyze the structure. Every method is applied to the case study through computer-based representations, that allow a friendly-use application of the principles explained. A particular closed-form approach based on an elasto-plastic material model and developed by some Belgian researchers is also studied. To compare the three methods, two different case study have been analyzed: i) a generic masonry arch bridge with a single span; ii) a real masonry arch bridge, the Clemente Bridge, built on Savio River in Cesena. In the analyses performed, all the models are two-dimensional in order to have results comparable between the different methods taken in exam. The different methods have been compared with each other in terms of collapse load and of hinge positions.

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The thesis deals with the concept of presumptions, and in particular of legal presumptions, in the context of national tax systems (Italy and Belgium) and EU law. The purpose was to investigate the concept of legal presumption under a twofold comparative perspective. After having provided a general overview of the common core concept of presumption in the European context, an insight in the national approach to legal presumptions was given by examining two different national experiences, namely the Italian and Belgian tax systems. At this stage, the Constitutional framework and some of the most interesting and relevant at EU level presumptive measures were explored, with a view to underlining possible divergences and common grounds. The concept of (national) legal presumption was then investigated in the context of EU law, with the attempt to systematize under a uniform perspective a matter which has been traditionally dealt with either from the merely national point of view or, at EU level, through a fragmented form. In this instance, the EU law relevant framework and the most significant EUCJ case-law, in particular in the field of customs duties, VAT, on the issue of the repayment of taxes levied in breach of EU law and in the area of direct taxation, were examined so as to construe the overall EU approach to national legal presumptions. This was done with the finality of determining if and to what extent a common analytical framework may be identified, from which were extracted certain criteria governing the compatibility of national legal presumptions with EU law.

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L'affermarsi della teoria della « imaginative geography » di Edward Saïd (Orientalism, 1978), nell'arco degli ultimi trent'anni, ha imposto un orientamento prettamente sociopolitico, gramsciano e foucaultiano alla critica del testo, proponendo un'unica soluzione interpretativa per un corpus eterogeneo di testi (scientifici e artistici, antichi e moderni) accomunati dal fatto di « rappresentare l'Oriente ». La costruzione europea dello spazio orientale, dice Saïd, non rappresenta solo un misconoscimento dell'Altro, ma una sua rappresentazione tendenziosa e finalizzata a sostenere la macchina dell'imperialismo occidentale. In particolare, la rappresentazione « femminilizzata » della geografia orientale (come luogo dell'exploit del maschio bianco) preparebbe e accompagnerebbe l'impresa di assoggettamento politico e di sfruttamento economico dei paesi ad Est dell'Europa. Se Orientalism ha conosciuto fortune alterne dall'anno della sua apparizione, negli ultimi anni una vera e propria corrente anti-saidiana ha preso forza, soprattutto in ambito francese. Attraverso l'analisi di circa trenta opere francesi, belga, inglesi e italiane del Novecento, questa tesi cerca di visualizzare i limiti teorici della prospettiva saidiana rivolgendosi a un esame della rappresentazione dello spazio urbano indiano nella letteratura europea contemporanea. Nello specifico, uno studio delle nuove strutture e dei nuovi modelli della femminilizzazione dello spazio orientale indiano cercherà di completare – superandolo in direzione di un « post-orientalismo » – il riduzionismo della prospettiva saidiana.